Hi Gurus,

Been a while, but I'm still around.

About to get the Vette on the road for the season. I've decided to address the oil leaks I've been looking at for the last couple of years. My mechanic took a close look at things for me last summer, and found I'm leaking from the pan gasket, rear seal, timing cover, and intake. The leak from the rear seal seems to be the worst, while the other points are not quite as bad.

My mechanic told me that if I was looking to take care of them all, it would probably save me a few bucks in labor if he just pulled the engine and went through everything on an engine stand. I'm seriously thinking about having it done this spring. The car is a '92 and in great condition otherwise and just about 78,000 on the odometer. I'm planning to keep the car at least a few more years and maybe longer, so I think it's worth investing a bit in it. Waiting on a quote from my guy for the work.

My question though, is if we're actually going to go through with pulling the engine, that would be a great time to look at doing a few other things. I was thinking a new water pump, new timing chain / gears, and also replacing the Opti. The Opti is original as far as I can tell. I'm not having any Opti-specific problems, so I'm thinking totally preemptive here.

So I'm kind of looking for "if it were my car..." type of input. Would you do the Opti? If so, what brand / parts source would you go with? I see Rock Auto has reconditioned AC/Delco units available. I was kinda' leaning in that direction.

Thoughts greatly appreciated.

Ron

I'd a least take it off and take it apart

check the cap & rotor

vent the cap like the later ones

check the bearings

May want to replace the waterpump & the front seals

What does he want to charge you for removing the engine? That's a lot of labor to pull the engine and replace gaskets. Then you hit the slippery slope of "while I'm in there".

As far as the opti, I doubt I would replace it. The OEM is way better than the aftermarkets. I'd do what Brian suggests - pull and inspect it, vent it, and replace the waterpump as a precaution. OEM optis are known to go over 150,000 miles when cared for.

IF IT AIN'T BROKE, DON'T FIX IT. COST ME MUCHO DINERO TO LEARN THAT; I OFFER THE LESSON FOR FREE.

Thanks for the input guys. I sent my mechanic an email with the list of things I'm considering. I told him the oil leaks were my primary concern, and that I'd really rather not have the engine come out. I asked him to give me a quote for fixing all the leaks for both scenarios...engine in and engine out. Still waiting for a reply. It would have to be a SIGNIFICANT savings for me to go with pulling the engine.

I'll take a cautious approach with the Opti. The timing cover leak means the Opti has to come off, and will also give us a visual on the timing chain and gears. We'll just wait and see what they both look like and go from there.

Changing the gaskets is certainly EASIER with the engine out...but might not be cost effective. Keep us posted.

Well, if it was my car, wait, it is my car.

Having gone thru this more than once and being in the middle of it again:

I would take an extremely close look at the rear leak, clean it up and determine IF the rear seal is leaking and how bad. The seal is a one piece and the trans or engine has to be pulled to replace it. If it's a couple drips per week, I wouldn't spend the money.

The front seals and pan gasket can be changed without pulling the engine but, the front of the engine may need to be jacked up some depending on where the factory located the front brake crossover line which can interfere with pulling the pan.

The front cover seals - ASK your guy if he's pulled the crankshaft hub on an LT1 before, there's a procedure using a long bolt that HAS to be used, a regular puller will not work and could damage the hub. (Procedure available on line)

And installing the front cover with the new seals takes a tool to protect one of the seals as you install the cover. I have the Kent-Moore tool but one can be made (again, thee how to is available on line).

Opti:

Yea, check the cap & rotor BUT that's just maintainence, NOT what you should be looking at to make a decision.

You need to look VERY CAREFULLY at the bearing, look for any dark brown material (rust) thrown out of that bearing. There will be black (lube) thrown out to the outside but, that's OK. The rust would not be OK.
And check the optical disc for any marks , it should also be perfectly flat with no waves. I wouldn't replace it if this looks good.

As Matt said, 150,000, yea, it's possible. And changing the opti is a 3 1/2 -4 hour job, not that hard.

The water pump is a $200 item, run it until it leaks, new gaskets to install are $3. I would however JB weld a plastic 90 degree fitting into the weep hole, and a small hose running over the opti so that a leak there won't get the opit wet.

Optis:

My $505 MSD lasted only 20k miles.
I bought a less expensive APR, it was bad right out of the box, throws a code but runs.

The GM (AC Delco) ? depends on the price but I seriously doubt that you'll find an NOS, most are referbs. Summit has the Delco for $466.

My next one will be from here:

http://petrisenterprises.com/optispark-distributor/

It's up to you on pulling the motor but it's a lot of money to spend on an $8,000 car.
If I was to spend the money on pulling the motor and planed to keep the car, I'd have the motor rebuilt while I was at it.

JMO

A lot of good input guys. Now I'm not so sure just how far I want to pursue this. Call me weird, but I've taken a pic of the oil spots the car has left after sitting all winter for the past two years.

2015...

2016...

The front of the car would have been oriented facing toward the top of each of the two pictures. So you can see where the leaks appear to be coming from both the front and back of the engine.

It's pretty apparent that the leak at the rear (rear main seal and/or pan gasket) has grown a bit. Though I am planning to keep the car a few more years at least, Bill's post got me to thinking. Not sure if I'm ready to sink $1.5k - $2k (my estimates) into an $8k car.

If these were your leaks would you be chasing them down?

And what's interesting too, is that during the driving season, I see no leakage at all. I guess the heat from regular use must keep the seals, well, 'sealed'. It's only when it sits for a minimum of several weeks that I see the above.

Oil can take weird paths when dripping. No guarantee the front leaks are from the front seal. Clean everything liberally and then add some uv dye to see where it is actually coming from. Wold suck to repair the main seal for no reason if it is the intake China wall....just sayin....

I have done optis on both my father's 94 and as soon as I got my 94, I did it before, I even put it on the road (didn't want to deal with it again like I had to with my father's) both cars have the MSD opti, coil and wires. His has had about 30k miles put on the new opti and mine has had about 6k Miles. So far so good and the car runs a lot cleaner. Much better spark. Well worth the 600 bucks to take care of the whole ignition system essentially. I didn't pull the motor to do either of them tho. Good luck!

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Well, even as much as I hate leaks.

I'd jack the side of the car up, hit the pan, X-member and trans with Simple Green, hose it off and enjoy driving the car.

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Yep, it can go anywhere.

If the cleanup is good enough, probably wouldn't even need the dye. Just look under there often.

I'd say that this leak is more of a nuisance than a problem.

Certainly not like the puddles of antifreeze under mine at the moment.

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No 2 problems are the same but mine (with about your mileage) was all pan gasket, the R-seal was fine. I did the timing cover ONLY because the pan was already off.

Check the torque on the intake bolts - some years ago I had an oil leak due to the bolts on the ends being a bit loose.